Re: Command extension suggestions

[Bean <bean123@126.com>]

On Thu, Jun 14, 2007 at 11:42:24AM +0200, Marco Gerards wrote:
> Bean <bean123@126.com> writes:
> 
> [...]
> 
> >> That sounds much cleaner IMHO.  But IIRC (md) is already in use by the
> >> RAID/LVM stuff ?
> >> 
> >
> > Maybe (mem) ?
> 
> When would this be useful?

You can use it to dump physical memory, for example,

od (mem)+2

dump first 1K of memory

od --skip-bytes=0x413 --read-bytes=2 (mem)

dump the word at 0x413.

I can't think of other use at the moment.

> 
> > Also, I don't know if GRUB2 kernel support initrd. You can start grub4dos
> > like this:
> >
> > kernel /grub.exe
> > initrd /aa.img
> >
> > Inside grub4dos, the initrd can be access using (rd). It would be nice if
> > grub2 support this kind of usage.
> 
> You can use the loopback command to do this, if you want to access a
> filesystem image.
> 
> loopback (loop) /foo/bar.img
> ls -l (loop)/
> 

Initrd can still be useful. In some case, it's not easy to access the boot
media, such as, cdrom or pxe. To boot from such media, you can either put
everything in core.img, or you can create a minimum core.img, and put other
files, like *.mod, grub.cfg, font, etc, in an initrd. The initrd can be
loaded along with core.img, using loader such as isolinux or pxelinux.

-- 
Bean <bean123@126.com>